Monitoring the parameter vector of regression models with time-to-event response in phase II processes

In most of the existing specialized literature, monitoring regression models are a special case of profile monitoring. However, not every regression model always represents appropriately a profile data structure. This is clearly the case of the Weibull regression model (WRM) with common shape parameter γ. Even though it might be thought that existing methodologies (especially likelihood-ratio (LRT)-based methods) for monitoring generalized linear profiles can also be successfully applied to monitoring regression models with time-to-event response, it will be shown in this paper that those methodologies work fairly acceptable just for data structures with 1000 observations at least approximately. It was found out that some corrections, often referred to as Bartlett's adjustments, are needed to be implemented in order to improve the accuracy of using the asymptotic distributional properties of the LRT statistic for carrying out the monitoring of WRM with relatively small and moderate dimensions of the available datasets. Simulation studies suggest that the use of the aforementioned corrections make the resulting charts work quite acceptable when available data structures contain 30 observations at least. Detection abilities of the proposed schemes improve as dataset dimension increases.     

Estimation of variance in bivariate normal distribution after the preliminary test of homogeneity

A preliminary test estimator of variance in the bivariate normal distribution is proposed after the Pitman–Morgan test of homogeneity of two variances. The bias and mean square error of the estimator are derived. The relative efficiency (RE) of the preliminary test estimator is studied. Computations and 3D graphs of RE for different parameters are analyzed. In order to get the maximum RE, recommendations of the significance level for the preliminary test are given for various sample sizes by using the max–min criterion.     

关注公民公平感——我国部分公民公平感调查报告

对我国部分普通民众进行的"公民公平感"问卷调查表明,人们在司法、医疗、住房、就业、教育、尊重和户籍制度等问题上,通过比较自己与他人、过去与现在、地区间与行业间,都对社会有着基本的认同与公平感受以及较强的纳税意愿。调查结果显示,在引起不公平感的诸多社会现象中,人们对普通百姓看不起大病重病、贫富差距拉大和普通百姓买不起房三大问题意见集中,并把对抗大病风险的医疗保障、缩小贫富差距和调控房价等方面的责任与期望赋予了政府。     

Improving variance function estimation in semiparametric longitudinal data analysis

We propose an efficient and robust method for variance function estimation in semiparametric longitudinal data analysis. The method utilizes a local log‐linear approximation for the variance function and adopts a generalized estimating equation approach to account for within subject correlations. We show theoretically and empirically that our method outperforms estimators using working independence that ignores the correlations. The Canadian Journal of Statistics 39: 656–670; 2011. © 2011 Statistical Society of Canada     

The matched pair sign test using bivariate ranked set sampling for different ranking based schemes

Bivariate rank set sample (BVRSS) matched pair sign test is introduced and investigated for different ranking based schemes. We show that this test is asymptotically more efficient and more powerful than its counterpart sign test based on a bivariate simple random sample (BVSRS) for different ranking schemes. The asymptotic null distribution and the efficiency of the test are derived. Pitman’s asymptotic relative efficiency is used to compare the asymptotic performance of the matched pair sign test using BVRSS versus using BVSRS in all ranking cases. For small sample sizes, the bootstrap method is used to estimate P-values. Numerical comparisons are used to gain insight about the efficiency of the BVRSS sign test compared to the BVSRS sign test. Our numerical and theoretical results indicate that using any ranking scheme of BVRSS for the matched pair sign test is more efficient than using BVSRS.     

进退两难:相对不起诉制度之博弈分析

相对不起诉制度是我国1996年修改后的<刑事诉讼法>对检察机关免予起诉制度废除后的产物.从10余年的司法实践过程来看,相对不起诉在检察机关应用较少,主要是体现了检察权对审判权的谦抑.从该制度最初的功能设计分析,相对不起诉是为处理刑事案件作适当分流而设计的,它应该是解决刑事案件中利益冲突的途径之一.长期的实践表明,该制度面临着许多矛盾,这些矛盾导致相对不起诉制度处于一个进退两难的境地.因此,从保护被害人权利来说,完善相对不起诉制度,使之成为刑事案件中利益冲突解决的正式途径,应该是新的刑事诉讼修改的一个重要内容.     

Estimation of a discriminant function from a mixture of two inverse Weibull distributions

The classification of a random variable based on a mixture can be meaningfully discussed only if the class of all finite mixtures is identifiable. In this paper, we find the maximum-likelihood estimates of the parameters of the mixture of two inverse Weibull distributions by using classified and unclassified observations. Next, we estimate the nonlinear discriminant function of the underlying model. Also, we calculate the total probabilities of misclassification as well as the percentage bias. In addition, we investigate the performance of all results through a series of simulation experiments by means of relative efficiencies. Finally, we analyse some simulated and real data sets through the findings of the paper.     

A one- sample test based on subsamples medians

Nonparametric test statistics are constructed by considering the medians in subsamples of appropriate size taken -from n independent observations. These tests are shown to be sensitive to both heavy and moderate tailed distributions.     

一般信任模式的跨部门差异及其中介机制: 基于2010年中国综合社会调查的研究

本文基于“市场”与“国家再分配”两种不同制度环境的讨论，利用中国综合社会调查2010年的数据，运用倾向值匹配方法处理潜在的选择性误差，考察了不同部门中个体的一般信任水平。结果显示，相比私有部门（外资企业和私营企业），在公共部门中工作的个体呈现了更高的一般信任水平。进一步的分析表明，政治参与水平和相对剥夺感作为中介于工作部门与一般信任水平之间的解释机制是显著的，在公共部门中工作的个体不仅在态度上对内在政治效能感有更高的认定，而且也能积极参与居委会社区的选举。这些特征极大提升了他们的一般信任水平。此外，公共部门中的个体在社会地位与经济地位上所持有的较低的相对剥夺感也有助于其建立更高的一般信任水平。     

Smooth goodness of fit tests for the weibull distribution with singly censored data

The smooth goodness of fit tests are generalized to singly censored data and applied to the problem of testing Weibull (or extreme value) fit. Smooth tests, Pearson-type tests, and the spacings tests proposed by Mann, Schemer, and Fertig (1973) are compared on the basis of local asymptotic relative efficiency with respect to the asymptotic best test against generalized gamma alternatives, The smooth test of order one Is found to be most efficient for the generalized gamma alternatives.